Re: [PATCH v3 5/8] irqchip/qcom-pdc: Configure PDC to pass through mode

[Maulik Shah (mkshah)]

On 6/30/2026 8:37 PM, Thomas Gleixner wrote:
> On Tue, Jun 16 2026 at 14:55, Maulik Shah wrote:
>> All PDC irqchip supports pass through mode in which both Direct SPIs and
> 
> All PDC variants support pass .. ??

Yes, It should be all PDC HW variants supports...I will update in v4.

> 
>> GPIO IRQs (as SPIs) are sent to GIC without latching at PDC.
>>
>> Newer PDCs (v3.0 onwards) also support additional secondary controller mode
>> where PDC latches GPIO IRQs and sends to GIC as level type IRQ. Direct SPIs
> 
> latches the GPIO interrupts and sends them to GIC as level type interrupts.

Sure, I will update in v4.

> 
>> still works same as pass through mode without latching at PDC even in
> 
> SPIs .. work the same as pass-through mode ....

Sure, I will update in v4.

> 
>> secondary controller mode.
>>
>> All the SoCs so far default uses pass through mode with the exception of
> 
> SoCs ... use pass-through 

Sure, I will update in v4.

> 
>> x1e. x1e PDC may be set to secondary controller mode for builds on CRD
>> boards whereas it may be set to pass through mode for IoT-EVK boards.
>> The mode configuration is done in firmware and initially shipped windows
>> firmware did not have SCM interface to read or modify the PDC mode.
>> Later only write access is opened up for non secure world.
> 
> .. for the non-secure ..
> 

Sure, I will update in v4.

>> +/**
>> + * qcom_pdc_gic_set_type: Configure PDC for the interrupt
>> + *
>> + * @d: the interrupt data
>> + * @type: the interrupt type
> 
> https://docs.kernel.org/process/maintainer-tip.html#struct-declarations-and-initializers
> 
> I'm sure I pointed you to that document before.

Yes, missed this place to follow. I will update in v4.

> 
>> + *
>> + * All @type are forwarded as Level type to parent GIC
>> + */
>> +static int qcom_pdc_gic_secondary_set_type(struct irq_data *d, unsigned int type)
>> +{
>> +	enum pdc_irq_config_bits pdc_type;
>> +	enum pdc_irq_config_bits old_pdc_type;
> 
> Chapter before the above ...

I will update in v4.

> 
>> @@ -449,8 +628,13 @@ static int pdc_setup_pin_mapping(struct device *dev, struct device_node *np)
>>  		if (ret)
>>  			return ret;
>>  
>> -		for (int i = 0; i < pdc->region[n].cnt; i++)
>> -			pdc->enable_intr(i + pdc->region[n].pin_base, 0);
>> +		for (int i = 0; i < pdc->region[n].cnt; i++) {
>> +			if (pdc_pin_is_gpio(i + pdc->region[n].pin_base) &&
>> +			    pdc->mode == PDC_SECONDARY_MODE)
>> +				pdc->clear_gpio(i + pdc->region[n].pin_base);
>> +
> 
> Requires guard(irqsave)(...)
> 

Yes, added in v4 within pdc->enable_intr().

Thanks,
Maulik